Magento2 - accessing helper in controller

Question

I have helper class that has constructor that takes following parameters: Context, Cart, Session, CollectionFactory. It derives from \Magento\Framework\App\Helper\AbstractHelper.

I would like to use this helper inside of my frontend controller but I don't know what to do to make my controller constructor called with extra parameters so that I could use them to initialize my helper class.

Point is - I would like to have access to Context, Cart, Session, CollectionFactory in controller that derives from \Magento\Framework\App\Action\Action.

Here is source code of my controller and part of the helper class:

<?php
namespace Something\Something\Controller\Index;
class Index extends \Magento\Framework\App\Action\Action
{
 protected $_pageFactory;
 public function __construct(
 \Magento\Framework\App\Action\Context $context,
 \Magento\Framework\View\Result\PageFactory $pageFactory)
 {
 $this->_pageFactory = $pageFactory;
 return parent::__construct($context);
 }
 public function execute()
 {
 echo $some_json_that_i_will_use_in_the_frontend;
 }
}

Helper:

<?php
namespace Something\Something\Helper;
use \Magento\Customer\Model\Session;
use \Magento\Checkout\Model\Cart;
use \Magento\Framework\App\Helper\Context;
use \Magento\Sales\Model\ResourceModel\Order\CollectionFactory;
use \Magento\Sales\Model\Order;
class Data extends \Magento\Framework\App\Helper\AbstractHelper
{
 private $cart;
 private $customerSession;
 private $orderCollectionFactory;
 public function __construct(
 Context $context, Cart $cart, Session $customerSession, CollectionFactory $orderCollectionFactory
 ) {
 $this->cart = $cart;
 $this->customerSession = $customerSession;
 $this->orderCollectionFactory = $orderCollectionFactory;
 parent::__construct($context);
 }
}

• Sukumar Gorai: Can you add your controller and helper file to your question?
• Mister Paszczakowski: I have edited my post and attached source code of controller and helper
• Sukumar Gorai: Why not you have injected the cart, session etc to your controller instead of helper? If you also need those in helper then you need to inject those both in controller and in helper. This will solve your issue.

Answer 1

You can use the below code for controller file:

<?php
namespace Something\Something\Controller\Index;
class Index extends \Magento\Framework\App\Action\Action
{
 protected $_pageFactory;
 protected $_cart;
 protected $_customerSession;
 protected $_orderCollectionFactory;
 protected $_scopeConfig;
 public function __construct(
 \Magento\Framework\App\Action\Context $context,
 \Magento\Framework\View\Result\PageFactory $pageFactory,
 \Magento\Checkout\Model\Cart $cart, 
 \Magento\Customer\Model\Session $customerSession, 
 \Magento\Sales\Model\ResourceModel\Order\CollectionFactory $orderCollectionFactory,
 \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig
 ){
 $this->_pageFactory = $pageFactory;
 $this->_cart = $cart;
 $this->_customerSession = $customerSession;
 $this->_orderCollectionFactory = $orderCollectionFactory;
 $this->_scopeConfig = $scopeConfig;
 return parent::__construct($context);
 }
 public function execute()
 {
 echo $some_json_that_i_will_use_in_the_frontend;
 }
}

• Mister Paszczakowski: Thats great, what about using scope config?: $this->scopeConfig->getValue(self::something, \Magento\Store\Model\ScopeInterface::SCOPE_STORE
• Sukumar Gorai: Check my updated answer.
• Mister Paszczakowski: Unfortunately I am getting this exception Uncaught ArgumentCountError: Too few arguments to function _construct
• Sukumar Gorai: When are you getting this error? During di compile?
• Mister Paszczakowski: I was trying to call constructor without compiling di, thank you so much!

Answer 2

 <?php
 namespace Something\Something\Controller\Index;
 class Index extends \Magento\Framework\App\Action\Action
 {
 protected $_pageFactory;
 protected $helper;
 public function __construct(
 \Magento\Framework\App\Action\Context $context,
 \Something\Something\Helper $helper
 \Magento\Framework\View\Result\PageFactory $pageFactory)
 {
 $this->helper = $helper;
 $this->_pageFactory = $pageFactory;
 return parent::__construct($context);
 }
 public function execute()
 {
 echo $some_json_that_i_will_use_in_the_frontend;
 }
}